Amid increasingly strained relations between the leadership of the Scottish and UK parties, Mr McDonnell told ITV a lack of enthusiasm was behind Owen Smith’s victory over Jeremy Corbyn in Scotland.
“In Scotland there hasn’t been the surge in membership and enthusiasm that we’ve had in the rest of the country, largely because a lot of the younger people and others went to the SNP, even on the left went to the SNP,” he said.
Mr McDonnell also defended his description of a Tory former minister as “stain on humanity” who peopled wanted to have “lynched” by insisting he was expressing “honest anger”.
Esther McVey sat on as he admitted he had sometimes “gone too far” but insisted it was better to be honest about his views. Ms McVey told the programme: “Whether it’s lynching me, whether it was assassinating Margaret Thatcher, whether it’s honouring the IRA... this is a man who links violence with politics.”
Labour former frontbencher Yvette Cooper called on Mr McDonnell to apologise and said his comments were “really, really not okay”.